1. Field of the Invention
This invention pertains generally to excavating, and more particularly to land clearing equipment including tree and stump removers. In a preferred manifestation, the invention is an apparatus suitable for rapid mounting on a skid-steer or other motorized earth-moving vehicle, which enables the uprooting of trees or digging of stumps. The apparatus includes a digging element that is generally knife shaped with teeth, serrations, or hooks.
2. Description of the Related Art
The harvesting of trees has origins that are older than recorded time, and likely originate at the origins of man himself. Trees provide a unique source of very long-chain, powerful cellulosic material which man has, since before recorded time, used for many diverse purposes. The long cellulosic fibers provide strength across large distances, while offering some limited flexibility. As a result, there is no material which is in wider use for construction of dwellings, or for the furniture found therein. Likewise, owing to the size and density of a typical tree, and the unique chemical structure of cellulose, there is an incredible amount of energy which may be released during combustion. The by-products from the complete combustion of cellulose are water and carbon dioxide, both which are omni-present and necessary for life. Consequently, trees serve as a vast, renewable source of energy. This energy has been used through all time as a source of heat, for cooking or comfort, but may also be used for commercial and industrial processes as well. There are literally many thousands of uses for trees and wood products today.
In addition to the direct benefit of the tree, there are also times when trees must be harvested not for the wood and wood products, but instead for access to the land. Many forested regions also provide land which is suitable for agricultural development, or for the placement of buildings or other human development. In such cases, not only will the above-ground portion of the tree be removed, but so will the stump. When land is cleared of both tree and stump, the soil may then be worked towards the end objective, without interference from either tree or stump.
In order to obtain the benefits of the tree and/or land, a person must first harvest the tree. In the not-so-distant past of the nineteenth century, this was most commonly done by lumber camps, which had many people that each fulfilled a different function. Saws were used to cut the tree, and axes to chop and direct the fall of a tree. Such technique is still used today, though the manual saws have been almost entirely replaced by gasoline powered chain saws. As those familiar with the history of lumber camps know, this was one of the most dangerous professions. Particular arrangements of trees were often referred to as “widow-makers”, since controlling the direction of the falling tree could be extremely difficult. Even with the modern chain saw, there is much hazard, not only from the tree, but from the saw as well. Many people are hospitalized each year for injuries that arise while operating a chain saw, some which are serious or life threatening.
As engines were developed and became available on wheeled vehicles, various artisans adopted these vehicles to the lumbering and tree clearing industries. Exemplary of such efforts are U.S. Pat. Nos. 831,715 by Franks; and 1,907,288 by Rarig, the teachings of each which are incorporated herein by reference. These vehicle-mounted tree and brush clearing saws were separately driven by the vehicle engine, and therefore moved in addition to vehicle movement, to replace the manual sawing required in the prior art.
Modern lumbermen no longer rely upon manual methods for the harvesting of trees, and instead utilize very large machinery, equipped with specialized devices that can both grasp and sever the tree at its base. With only a few minutes of time, and with very little risk to the operator, even very large trees may be harvested at their base and then stacked onto a semi-trailer or the like for removal from the forest.
While modern lumbering is almost entirely performed using very large and specialized equipment, artisans have also designed apparatus for the removal of trees using bulldozers and like machinery, most commonly for the purpose of rapidly clearing land but also for lumbering. Bulldozers are commonly used for construction and earth working, and provide a great deal of power and weight. However, they are not well adapted at moving either trees or brush, and so the land is normally first cleared of trees and brush, and then the earth is worked. To facilitate removal of trees and brush, while taking advantage of existing equipment, and either for land clearing or lumbering, a number of bulldozer or vehicle-mounted tree and brush clearing saws have been devised that travel with the vehicle. Exemplary patents, the teachings of each which are incorporated herein by reference, include U.S. Pat. No. 2,769,278 by Wassell et al; U.S. Pat. No. 2,821,217 by Shald; U.S. Pat. No. 3,004,570 by Clayton et al; U.S. Pat. No. 3,033,253 by Purdy; U.S. Pat. No. 3,415,296 by Frankenberg et al; U.S. Pat. No. 3,809,135 by Dove; U.S. Pat. No. 4,018,255 by Diggs; U.S. Pat. No. 5,950,699 by Dove; and U.S. Pat. No. 6,439,279 by Underwood.
While the modern lumber industry equipment is both highly time-efficient and relatively very safe for the operators, lumbermen need not give any consideration to the removal of stumps. The land may simply be replanted, if not naturally then by man, and then allowed to redevelop once more into a forest for future lumber harvests. Consequently, the lumber industry has not been much concerned with the removal of stumps. In contrast, where the land is being cleared for some other use, the tree stump must also be removed. While the foregoing vehicle-supported saws disclose removal of trees and brush, they too fail to disclose the removal of the stumps that will be left behind. These stumps will interfere with the working of the earth, and so should preferably be removed.
To facilitate removal of tree stumps and roots, artisans have developed various additional equipment and attachments. These apparatus would most commonly be used subsequent to the tree and brush clearing, but prior to substantial additional earth working. Such apparatus is illustrated by the following front- and rear-mounted rooters, the teachings of each which are incorporated herein by reference. Exemplary of front mounted rooters are U.S. Pat. Nos. 2,281,928 by Fletcher; 2,674,818 by Carnes; 2,716,823 by Mullin; 2,806,682 by Ankersheil; 2,835,992 by Flemer III; 2,837,844 by Launder; 2,852,875 by Bierwith et al; 2,882,622 by Howard; 2,912,774 by McCrary; 2,932,100 by Goethe; 2,985,973 by Struemph; 3,044,192 by Moore; 3,283,426 by Payne; 3,325,927 by Mullin; 3,887,015 by Kelley; 4,676,013 by Endo; 6,308,440 by Mueller; and 6,401,831 by Bouchard. Exemplary of trailing rooters are U.S. Pat. Nos. 686,153 by Smith; 2,439,743 by McEwen; 3,120,281 by Peveler et al; and 3,295,612 by Mayo et al. Additional patents illustrate various cutting tips and attachments designed to cut parallel to the ground, either attached directly to a bucket or instead. Exemplary of this approach are U.S. Pat. Nos. 2,934,109 by Bles; 3,084,727 by Basharn; 3,215,174 by Billings; 3,289,331 by Freeman; 3,351,108 by Hammonds; and 4,094,348 by Wolf, the teachings of each which are incorporated herein by reference.
A number of artisans have proposed various large, vehicle-supported saws that are designed to not only cut through the tree, but also the earth. Exemplary of such technique, the teachings which are incorporated herein by reference, are U.S. Pat. Nos. 3,534,487 by Arnaz; and 2,746,492 by DeHardit. However, powered saws are little match for the rocks and boulders that all too often become entwined within a tree root ball. When such rocks and boulders are encountered, the operator will lose much time and patience, as the saw is repeatedly broken and repaired. Furthermore, while power saws may offer conveniences once the tree is felled, these saws are also very expensive, and also quite dangerous to operate, owing in no small part to the risk of flying debris, including broken chains, teeth or other pieces from the saw.
Rather than pay for the various equipment described herein above, and make the multiple passes through the land to accomplish the desired clearing and stump removal, many persons and companies have instead relied solely upon very large earth working machines, such as bulldozers or the like, typically provided with large plows or blades, much weight, and very large engines, to clear the land. When using a large and powerful machine like a bulldozer, smaller trees may simply be pushed over. For trees too large to directly topple, tree roots are first uncovered by plowing down into the ground, and then the tree is pushed over using the blade. Finally, remaining roots are removed by plowing down into the ground. Unfortunately, as the roots are uncovered, the operator must traverse the same area that has just been uncovered. This means that the hole that was dug to expose the roots acts as a hole that must be driven through to continue with the digging and toppling effort.
As will be appreciated, this “brute force” technique requires very large equipment which is not reasonably owned by most land-owners or even smaller construction companies. Further, even where a company can economically justify such a machine, the transport to and from a job site is, in and of itself, difficult, expensive and somewhat dangerous, due to the large size and weight of the machine. Finally, the relatively larger equipment that is required to remove the tree also requires much open space to operate in, and will disturb large areas of land during the tree removal process.
To attempt to overcome the aforementioned limitations of the prior art, one group of artisans have devised various shovels and scoops which may be attached to various motive equipment. Exemplary of these, the teachings which are incorporated herein by reference, include U.S. Pat. Nos. 4,903,418 by Loudon; 5,901,479 by Langdon; 5,909,714 by Stoner; and 6,561,108 by Fisher. Another group has attempted to provide attachments to the existing shovels that enhance their performance. Such devices include various ripper teeth that are added to the shovel or bulldozer blade, such as the sharp blades illustrated in U.S. Pat. Nos. 2,187,707 by Kane; 5,901,477 by Weaver; 3,143,813 by Wells; and 2,626,468 by Dobrinich, Jr. An additional noteworthy attachment is illustrated in U.S. Pat. No. 2,840,932 by Breyer, entitled “Earth and Material Handling Implement”. This patent describes a pointed implement emanating from the center of a front-mounted bulldozer blade, designed for use as a rooter and a tipping implement. As useful as the Breyer concept may be in the tipping of trees, there is nothing provided to assist with the severing or removal of roots, other than the shear power and weight of the vehicle.